90 ELECTRIC LIGHTING. 



By a little consideration of the way in which the induced 

 ring is arranged it will be easily seen that it is placed under 

 the best possible constructive conditions. In fact, as each 

 section is separate, it may be removed without disturbing the 

 rest, and therefore the wire may be wound without any diffi- 

 culty. Those who are acquainted with the difficulties of 

 winding the wires on the Gramme ring will readily appreciate 

 this advantage. In another way the building up of the core 

 by juxtaposed laminae, which may be punched out at one 

 stroke, is an enormous advantage, for this system dispenses 

 with the precision necessary in the construction of these rings, 

 which it is always difficult to keep quite round. Finally, there 

 is neither commutator nor collector in the machine, and there- 

 fore there is no loss of current. 



We have seen that the currents supplied by this machine 

 are able to light three or four Jablochkoff candles ; but they 

 are also able to light regulators, and in this case the carbons 

 may be separated to the extent of 5 centimetres without 

 extinguishing the light. These results are certainly important. 



According to an interesting article by Demoget, in the 

 journal La Lumiere Electrique of the i5th July, 1879, it would 

 appear that the principle of the above-named machine was 

 discovered long before De Meritens, and that as early as the 

 year 1872 he had constructed a very similar machine, which 

 was described in a sealed packet deposited at the Academic 

 des Sciences at the meeting of the 20th January, 1875, an( ^ 

 that this machine had yielded remarkable results. Drawings 

 of the machine are given in the article we are referring to, 

 but on inspecting them it appears to us that the electro- 

 magnets of the induced ring were not insulated from each 

 other by non-magnetic substances, and in this consists one 

 of the great advantages o De Meriteps' iracbine. 



Wallace Former's Machine. This machine, not pre- 

 viously known in Europe, suddenly acquired some notoriety 

 in consequence of the panic on the Stock Exchange occa- 



